PORTLAND, Ore. — Eugene Police Officer Dan Baker drove a blue SUV and set off sirens to clear cars in front of him at traffic lights. He pulled over motorists — though it's unclear if he ever gave out tickets. And when he stopped by a youth shelter as a volunteer, he came in full uniform.

There's just one problem: There has never been an Officer Dan Baker in the Eugene Police Department.

Police in Oregon's second-largest city say the man with the badge was Daniel S. Alloway, and investigators are now trying to piece together at least a year of his alleged exploits while posing under the guise of an officer of the law.

"In one respect, I think he considers himself a public servant," said Eugene police Sgt. Scott McKee. "There's admissions by him, in his own mind, that he was doing a service."

McKee said Alloway acknowledged the impersonations under questioning Thursday night. He was arraigned Friday on one count of criminal impersonation, and police said they expect to file at least two dozen more charges.

Alloway was assigned a public defender and didn't enter a plea Friday. The Public Defender Services of Lane County did not immediately return a call seeking comment.

Authorities fear the victims of Alloway's alleged transgressions could go beyond the department's reputation. McKee said Alloway's uniform, badge, handcuffs and radio could have easily convinced anyone, including the 15- to 20-year-old boys at the youth shelter, that he had the power to arrest and charge them.

"People get automatic credential with the public," McKee said. "Somebody could use that to isolate a person, a 16-year-old, and that is dangerous."

Alloway, 39, was no stranger to being an authority figure. He is an active-duty member of the Oregon Army National Guard's Alpha Company, 2-162 Infantry Battalion, headquartered in Cottage Grove, Ore.

He was deployed three times to Iraq, in 2004, 2007 and 2009, serving a year tour each time. An Oregon Military Department spokesman said Alloway received service awards for each tour.

He also works a day job as a security guard. That job may have given him access to authentic-looking badges and a utility belt that included a Taser, handgun, pepper spray, radio and handcuffs, said Eugene police spokeswoman Melinda McLaughlin.

Police said they started receiving information from people in the community that something about "Officer Baker" wasn't right. That led to Alloway's arrest Thursday afternoon, which was not without drama.

No one answered the door when local police and Federal Protective Service officers arrived at Alloway's Eugene apartment. They later said they heard a gun being loaded from behind a locked door, but when they broke out a window, Alloway was missing.

He was on a county bus and out of cellphone range but returned calls from the police and was arrested a short while later in downtown Eugene.

Inside the apartment, McKee said police found several shoulder patches from various law enforcement agencies, framed like artwork.

One complication to the investigation was pure happenstance. Baker is a common name for Willamette Valley police officers: One family featured two Eugene police officers and one longtime Springfield officer.